Absorption and Emission Lines in Real Stars. information to help you identify the elements and reclassify the stars in the table above. When the atom goes back to its ground state, either directly or via intermediate energy levels, photon of only certain frequencies are emitted due to the discrete energy levels. 1- gravitational field of earth. half the maximum intensity ! Thus, the letters used by Fraunhofer to identify the lines have no relation to chemical symbols nor to the symbols used to designate the spectral … The intensity of a spectral line at a given frequency is related to the net rate of absorption (or emission) at that frequency. Some Fraunhofer lines were known to originate in absorption in the Earth's atmosphere. The last phenomenon that causes broadening of spectral lines is the collisions between excited atoms which can become predominant in high-density gas plasma emissions (high pressures). It is possible to relate the degree of splitting to the strength of the external magnetic field and astrophysicists can obtain information about a star's magnetic field distribution. Answer (1 of 1): A spectral line results from an excess or deficiency of photons in a narrow frequency range,compared with the nearby frequencies.Spectral lines are the result of interaction between a QUANTUM SYSTEM(usually Atoms,but sometimes Molecules or Atomic Nuclei)and single PHOTONS. Figure 02: Helium Emission Spectrum. r/explainlikeimfive: Explain Like I'm Five is the best forum and archive on the internet for layperson-friendly explanations. of the spectral line Δν could be! It is the spectrum obtained from sodium light. This causes the spectral lines to become split and is called the Zeeman Effect. for an emission line, width! Atoms and molecules can emit and absorb radiation at distinct wavelengths, causing the appearance of spectral lines. For most elements, there is a certain temperature at which their emission and absorption lines are strongest. Line spectrum can create an absorption spectrum or an emission spectrum. An emission line occurs when an electron drops down to a lower orbit around the nucleus of an atom and looses energy. Don't Panic! no line is observed. These lines are caused by the Sun's atmosphere absorbing light at certain wavelengths, causing the intensity of the light at this wavelength to drop and appear dark. Unlike in hydrogen, there are electron-electron repulsions and different nuclei-electron attractions in … Some compounds, like titanium oxide, only appear in the spectra of very cool stars. A spectral line is like a fingerprint that can be used to identify the atoms, elements or molecules that are present in a star, galaxy or cloud of gas. Details of definition donʼt matter - important to see what causes! Ask Question Asked 4 years, 5 months ago. And you'd still get spectral lines, because the sun isn't a perfect black body (nothing is, aside maybe from black holes). These are now known as spectral lines. 4- motion of galaxies away from us. What are the causes of splitting of spectral lines? There are mainly two types of spectra as continuous spectrum and line spectrum. Δν ν e.g. In this case, the spectral line profile is not Gaussian but Lorentzian, characterized by … They result when emitted light is partially absorbed by matter, usually a gas. An emission line will appear in a spectrum if the source emits specific wavelengths of radiation. 2- gravitational field of the sun. of the line.! What causes spectral lines is energy being emitted when "excited" electrons move from one energy level to another. Spectral Lines. Line emission and absorption spectra. Emission lines occur when the reverse process happens. ), and the associated temperature absorption in the ultraviolet part of the spectrum a temperature. 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